title: Endoscope-assisted spinal decompression surgery for lumbar spinal stenosis.
abstract: OBJECTIVE
  The authors undertook this study to document the clinical outcomes of microendoscopic laminotomy, a minimally invasive decompressive surgical technique using spinal endoscopy for lumbar decompression, in patients with lumbar spinal stenosis (LSS).
  
  
  METHODS
  A total of 366 patients were enrolled in the study and underwent microendoscopic laminotomy between 2007 and 2010. Indications for surgery were single- or double-level LSS, persistent neurological symptoms, and failure of conservative treatment. Microendoscopy provided wide visualization through oblique lenses and allowed bilateral decompression via a unilateral approach, through partial resection of the base of the spinous process, thereby preserving the supraspinous and interspinous ligaments and contralateral musculature. Clinical symptoms and signs of low-back pain were evaluated prior to and following surgical intervention by applying the Japanese Orthopaedic Association (JOA) scoring system, Roland-Morris Disability Questionnaire (RMDQ), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), and 36-Item Short Form Health Survey (SF-36). These items were evaluated preoperatively and 2 years postoperatively.
  
  
  RESULTS
  Effective circumferential decompression was achieved in all patients. The 2-year follow-up evaluation was completed for 310 patients (148 men and 162 women; mean age 68.7 years). The average recovery rate based on the JOA score was 61.3%. The overall results were excellent in 34.9% of the patients, good in 34.9%, fair in 21.7%, and poor in 8.5%. The mean RMDQ score significantly improved from 11.3 to 4.8 (p < 0.001). In all categories of both JOABPEQ and SF-36, scores at 2 years' follow-up were significantly higher than those obtained before surgery (p < 0.001). Twelve surgery-related complications were identified: dural tear (6 cases [1.9%]), wrong-level operation (1 [0.3%]), transient neuralgia (4 [1.3%]), and infection (1 [0.3%]). All patients recovered, and there were no serious postoperative complications.
  
  
  CONCLUSIONS
  Microendoscopic laminotomy is a safe and very effective minimally invasive surgical technique for the treatment of degenerative LSS.
authors.affiliation: Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Minamide
authors.forename: Munehito
authors.initials: M
authors.lastname: Yoshida
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamada
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: Masaki
authors.initials: M
authors.lastname: Kawai
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Maio
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hashizume
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwasaki
authors.forename: Shunji
authors.initials: S
authors.lastname: Tsutsui
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019299:Decompression, Surgical; D004724:Endoscopy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007796:Laminectomy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D017116:Low Back Pain; D008159:Lumbar Vertebrae / Q000601:surgery; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D011183:Postoperative Complications / Q000209:etiology*; D012720:Severity of Illness Index; D013130:Spinal Stenosis / Q000601:surgery*; D016896:Treatment Outcome